Recent mobile electronic devices are often requested to have various functions. A rotary switch is used as one means for operations of the functions. Thus, there are various requests for the rotary switch, such as the number of switches, relative timings (relative angle positions) of opening/closing (on/off) of each switch, combination of opening/closing of a plurality of switches, or operation feeling (click feeling) correspondingly to various operations.
FIG. 7 shows an example of a conventional rotary switch disclosed in Patent literature 1. In this conventional example, a circular housing recess 230 is formed at a center of a substantially square insulation body 110, and there are formed on a floor surface of the housing recess 230, an upright support shaft 240 at a center thereof, a ring-shaped common contact piece 290 surrounding the support shaft 240, and a plurality of fixed contact pieces 220 circumferentially arranged outside the common contact piece 290. The common contact piece 290 and the fixed contact pieces 220 are extended to a side edge of the insulation body 110 to form external terminals.
A rotating operation knob 120 includes an operation shaft 570, and an annular click plate 440 integrally formed with the operation shaft 570, and steps 490 and recesses 510 are alternately formed at regular angular intervals in an upper surface of the annular click plate 440. A rotating contactor 130 is secured to a lower surface of the annular click plate 440, and the rotating operation knob 120 is rotatably supported by the support shaft 240 and housed in the housing recess 230 in the insulation body 110.
The circular rotating contactor 130 formed by stamping a spring metal plate has a window at a center thereof, and a forked common slider 790 is formed to protrude on opposite sides of the support shaft 240 in the window. Each tip of the common slider 790 is brought into elastic contact with the common contact piece 290. Middle parts of two arcuate contact pieces formed by circumferentially slitting a peripheral edge of the rotating contactor 130 protrude downward to form switching contacts 680, and the switching contacts 680 slide on the arranged fixed contact pieces 220 and are brought into elastic contact with any one of the fixed contact pieces 220.
A ring-shaped leaf spring 140 is placed on the annular click plate 440 of the rotating operation knob 120. The ring-shaped leaf spring 140 has fixed terminals 830 extended outward from an outer peripheral edge at two points on a diameter thereof. Each fixed terminal 830 is bent 90 degrees downward at an intermediate part, and inserted and secured into an engaging hole 250 formed in each of opposite corners in an upper surface of the insulation body 110.
The ring-shaped leaf spring 140 has engaging protrusions 840 formed to protrude downward at two points on a diameter perpendicular to the diameter passing through the two fixed terminals 830, the engaging protrusions 840 climb the steps 490 in the annular click plate 440 against a spring force by rotation of the rotating operation knob 120, and fit in the recesses 510 by the spring force, thereby causing click feeling in a rotating operation of the rotating operation knob 120.
A substantially square metal case 150 is configured so that the operation shaft 570 protrudes outward through a shaft hole 920 formed at a center thereof, closes the housing recess 230 in the insulation body 110 from above the ring-shaped leaf spring 140 and is secured to the insulation body 110.